Cladding mold system

ABSTRACT

Improved mold system for cladding an elongated metallic rail element and the like wherein a unique biasingly mounted cladding die is employed which automatically adjusts itself to the contour of the rail despite variations in such rail contour as the rail moves past the die during cladding.

United States Patent 1 I 1 3,712,367 Plichta 1 Jan. 23, 1973 I 1 CLADDING MOLD SYSTEM 3,396,778 8/1968 Jensen et al. ..164/86 x [75} Inventor; Dietmar G. Plichm, Oakland Calif. 3,544,737 12/1970 Nowak ..250/108 [73] Assignee: Kaiser Aluminum & Chemical Cor- FOREIGN PATENTS OR APPLICATIONS poration, Oakland, Calif. 1,441,374 4/1966 France ..164/275 [22} Flled: Feb. 1971 Primary ExaminerR. Spencer Annear [21] App1.No.: 114,634 Attorney-Paul E. Calrow, Harold L. Jenkins and Elmer E. Goshorn [52] US. Cl ..l64/275, 164/87 [57] ABSTRACT [51] int. Cl. ..B22d 11/00 58 Field of Search ..164/82, 86, 273 R, 275 Improved mold System for Cladding elongated metallic rail element and the like wherein a unique [56] References Cited biasingly mounted cladding die is employed which automatically adjusts itself to the contour of the rail UNITED S A PAT TS despite variations in such rail contour as the rail moves past the die during cladding. 2,310,893 2/1943 Brenner ..l64/86 3,134,150 5/1964 Parke et a1 ..164/86 X 16 Claims, 6 Drawing Figures PATENTEDJAH23 1975 3,712,367

SHEET 1 [IF 3 [NV 1 OR DIETMAR G. CHTA M J'WW PATENTEDJAHZBISYS 3.712.367

sum 2 [1F 3 INVENTOR. DIETMAR G. PLICHTA PATENTEDJAH23I975 3,712,367

MGISO I50 F I G. 5 INVENTOR DIETMAR G. PLICH TA maM CLADDING MOLD SYSTEM BACKGROUND OF THE INVENTION ty characteristics such as aluminum. It is important in fabricating such bimetallic rails to produce rails wherein the aluminum cladding has a substantially uniform thickness or cross section from one end of a rail to the other.

The instant invention can be advantageously used with the equipment of co-pending U.S. Pat. application Ser. No. 881,l69, and filed Dec. 1, 1969 to Richter et al. and assigned to the Assignee of the instant application for a cladding mold system to produce the clad rail of the aforementioned U.S. Pat. No. 3,544,737 at mass production rates as well as a plurality of such rails simultaneously at a plural die casting station. The teachings of the instant invention can also be used to upgrade the mold equipment of U.S. Pat. Nos. 2,310,893 and 3,134,150.

The mold system of the instant invention is generally comprised of at least one cladding die device and a die mounting apparatus for positioning the die in predetermined spaced relationship relative to the rail being clad. A biasing mechanism is advantageously interposed between and interconnected to the cladding die and the mounting apparatus for enabling slidable yet yieldable engagement of the die with a selected part of the rail workpiece irrespective of geometrical variations in the workpiece contour and without interfering with the continuous advancement of the workpiece past the cladding die during casting of clad material directly between the die and the workpiece and on the workpiece. Such biased mounting of the cladding die assures formation of clad material on a workpiece without excessive exudation of clad material between the die and the workpiece during operation of the mold system whereby rails having uniform cladding characteristics will be produced.

SUMMARY OF THE INSTANT INVENTION A primary purpose of the instant invention is to provide an improved cladding mold system such as for constantly cladding an apertured I-shaped steel rail workpiece with a metal having superior electrical conductivity such as an electrical grade of aluminum so as to form a bimetallic electric rail element for anelectric railway.

The cladding mold system is generally comprised of a mold assembly and a feeder for advancing a workpiece past the mold assembly. If desired, a guide device can be disposed on the inlet side of the mold assembly for generally aligning and maintaining alignment of the workpiece with respect to the mold assembly upon advancement ofthe workpiece therethrough.

The mold assembly includes a cladding die and a mounting apparatus connected to the cladding die for moving the die from a retracted position to an advanced position and for mounting the die in a predetermined spaced relationship relative to certain parts of the workpiece during passage of the workpiece to and through the mold assembly so as to form a substantially uniformly clad workpiece from end to end.

If the rail workpiece is an I-beam with the die fitting within a channel recess of the rail and when and if the flanges of the rail shift in a direction towards and into contact with the die due to geometrical variations in the rail cross section the die can give and more sideways, etc. since it floats relative to the rail and does not frictionally engage and bind the rail.

The mounting apparatus further includes an adjustable stop element for precisely positioning the cladding die in its proper advanced position relative to selected parts of a workpiece rail such as within the recess thereof. Even though the present mold system is particularly useful for aluminum cladding of an I-shaped and apertured steel rail workpiece it is not intended to be limited thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmented perspective view with parts broken away of a preferred embodiment of a mold system of the instant invention for producing a clad rail element;

FIG. 2 is an enlarged fragmentary plan view with parts added and other parts broken away as taken along line 2-2 of FIG. 1 and illustrates the mold system of the instant invention provided with a plurality of cladding die stations, e.g. two, for simultaneously cladding two workpieces;

FIG. 3 is an enlarged fragmentary plan view taken along line 33 of FIG. 2;

FIG. 4 is an enlarged cross-sectional view with parts added as taken along line 4-4 of FIG. 2;

FIG. 5 is an enlarged end elevational view with parts broken away as taken along line 5-5 of FIG. 2; and

FIG. 6 is an enlarged cross-sectional view taken along line 6-6 of FIG. 2.

DETAILED DESCRIPTION With further reference to the drawings and in particular FIG. 1, a preferred embodiment of an improved mold system 10 of the instant invention is illustrated for castably cladding aluminum material I to opposed sides and within the channels of an apertured I-shaped steel rail workpiece or base element w upon advancement of the workpiece into, through and out of a mold station to form a clad rail element E of bimetallic construction. Base element w includes a pair of opposed flanges 12 and a web 14 and a series of spaced apertures 16' are provided along the length of web 14' of workpiece Ell. During operation of system 10 cladding Q is preferably directly cast upon opposite sides of workpiece'web 14' between the ends of the base element E and within the opposed channels or recesses so as to form bimetallic element \l having opposed major clad portions 18' and a series of rivet portions 20' disposed within and substantially filling the series of apertures 16' of the base element in the manner shown in FIG. 1. Since the particular manner in which the opposed major clad portions 18 and riveted portions 20' are cast and mechanically bonded to opposite sides of the web 14 of base element E are fully discussed in U.S. Pat. No. 3,544,737 and do not constitute an essential part of the instant invention, no further discussion of such casting and bonding cladding C to rail W is believed necessary.

Workpiece rail w is normally manufactured from a length of rolled steel bar stock. The rolled rail which is usually on the order of 40 to 60 feet long ordinarily has geometrical variations along its length. For instance there can be differences in thickness between various sections of the rail and slight helical twists of certain sections of the rail about its longitudinal axis, etc. These geometrical variations along the length of the rail are usually caused during the rails manufacture by different cooling rates along the rail length and sometimes by different metallurgical characteristics exhibited by the various parts of the rail. The improved mold system of the present invention enables the casting of clad material Q in a continuous and substantially uniform fashion to opposite sides of a rail E and within its opposed recesses between the ends thereof so as to form clad element \ill in an improved manner as will now be described irrespective of such geometrical variations, etc.

The system is generally comprised of a mold assembly l2 and an overhead chain-type hoist 14 for lowering a rail workpiece into, through and then lifting the rail out of the overall workpiece receiving and cladding opening 16 of the mold assembly. As indicated in FIG. 2 the mold assembly can be made up of a plurality of openings 16 (only two of which are shown in FIG. 2) so as to define a corresponding series of cladding stations Cladding devices 18 are arranged in opposed pairs at each cladding station A framework 20 of the cladding mold assembly slidably supports a pair of dies 18 at each station. An adjustable die mounting mechanism 22 is connected to framework 20 and is journably connected to each die at a station The mounting mechanism operates to cause advancement of the pair of opposed dies 18 at a given station from retracted positions with respect to framework 20 to advanced positions with respect thereto and vice versa as best shown in FIGS. l-2. When a pair of dies 18 at a station are in their advanced positions with respect to framework 20, they operate to define between the dies the upper reduced end of overall cladding opening 16. Upon advancement of the leading end of a workpiece E between the advanced pair of dies 18 each die tits in the recess between the opposed flanges of the workpiece on opposite sides of the workpiece web. Each die 18 is also spaced at a predetermined distance A from the adjacent side of the web of a workpiece E as the workpiece advances past the dies located in their forward positions. At the same time that a die is in an advanced position each opposed side of the die is normally spaced from the adjacent inner flange surface of a workpiece E by a gap K of preselected size which it is desirable to maintain throughout the cladding operation.

A biasing mechanism 28 is advantageously interposed between and interconnected to a die I8 and mounting apparatus 22 for enabling slidable and yieldable engagement of a die 18 with an adjacent inner flange surface of a rail E should the rail tend to shift in a direction laterally of and towards the die due to geometrical variations along the length of the rail upon advancement of the rail past the die during operation of system 10. As will become more apparent hereinafter a biasingly mounted die 18 advantageously acts to maintain its spaced relationship A with a workpiece E while at the same time preventing excessive exudation of cladding between either side of the die and the adjacent inner flange surface of the workpiece during the cladding operation. Moreover, a biasingly mounted die in acting to maintain a selected spaced relationship A between the die and the web of a workpiece in turn acts to maintain the thickness of a major clad portion 18' of a clad workpiece \l' substantially uniform across the width of such clad portion whereby the clad rail when used to conduct electricity will have substantially uniform electrical conductivity characteristics from end to end.

If desired, mold system 10 can be provided with a guide device 30 disposed on the inlet side of the mold assembly 12 for guiding a workpiece during advancement of the workpiece through the cladding opening in order to generally align the same with the opening.

As indicated in FIGS. 1-2 the equipment making up system 10 is generally the same and symmetrical'on each side of transverse axis 29 of the mold assembly 12. By reason of this symmetry, etc. only one die device 18 and mounting apparatus 22 disposed on one side of the transverse axis 29 of the mold assembly at a given station will be described unless otherwise specified.

One advantageous embodiment of the mold system 10 of the present invention comprises framework 20 provided with an upstandinghollow cylindrical shaped column 32 only part of which is shown in FIG. 4 for surrounding a well 33 that receives the leading portions of a workpiece Vl An annular cap flange 34 and a support plate 36 are connected to the upper end of column 32 in the manner shown in FIG. 4. A plurality of lugs 38 (only one of which is shown in FIG. 4) are affixed to various side portions of plate 36 and the lower end of a lug 38 overlaps the adjacent side portions of flange 34. A cap screw 40 is passed through an opening in the lower end of a lug 38 until the threadedend of the screw abuttingly engages a side portion of plate 34. When cap screws 40 of all the lugs 38 are drawn up against flange 34, plate 36 is secured to plate 34. An annular reinforcing flange element 42 can be affixed to adjacent intersecting outer surface portions of plate 34 and column 30 in the manner depicted in FIG. 4.

Plate 36 is provided with apertures 44 that ultimately form part of the lower end of the overall cladding opening 16 of mold assembly 12 at a station An aperture 44 has a length and width much greater than the thickness and width of a rail E. The lower end of an aperture 44 is in direct open communication with the interior openings of well plate 34 and column 32.

In a further advantageous embodiment of the invention a die device 18 includes a carriage 46 and a die element 48 adjustably connected thereto. Carriage 46 is formed from a plate of rectangular shape in cross section. For a reason that will become more apparent hereinafter the top side of carriage 46 is provided with an upwardly facing U-shaped groove 50 that cuts across carriage 46. The bottom 47 of carriage 46 is disposed in slidable engagement with the top of support plate 36 adjacent an opening thereof. The outer end of carriage 46'may be beveled in the manner indicated at 52in FIGS. 2 and 4.

Die element 48 mounted on carriage 46 is advantageously comprised of an upstanding outer support plate 54 of block-type configuration and a cladding plate 56 suitably affixed thereto. Die plates 54 and 56 have corresponding widths and lengths as indicated in FIGS. 2 and 4. As noted particularly in FIG. 2 plates 54 and 56 of the die element 48 of overall die 18 have widths somewhat less than the distances between the opposed workpiece flanges when these plates are spaced at a predetermined distance A with respect to the adjacent opposed side of the web 14' of a workpiece w during operation of the equipment of system 10. The upper end of outer plate 54 of a die 18 is cut away to define a U-shaped outer groove 58 all as indicated in FIGS. 2-4 while the upper end of inner plate 56 of a given die is similarly cutaway to define an inner groove 60 of somewhat keyhole configuration which has a necked-in upper portion 61 and an enlarged U- shaped lower grooved portion 62 in the manner best illustrated in FIG. 3. The enlarged lower U-shaped portion 62 of inner keyhole groove 60 is in direct and full communication with the lower end of outer U-shaped groove 58. The U-shaped side edge portions 64 of die plate 56 are connected to the upper necked-in groove 61 by opposed shoulders 68, all as indicated in FIG. 3.

A U-shaped trough or sleeve 69 is inserted in the bottom of groove 58 and the bottom of the enlarged U- shaped portion 62 of inner groove 60. The inner end face of trough element 69 when inserted in the grooves 58 and 62 as aforedescribed is disposed in planar alignment with clad applying inner surface 70 of plate 56. The opposed and upper edges of trough 69 at the inner end thereof are located in abutting engagement with opposed shoulders 68 of plate 56 thereby assuring that trough 69 is properly seated against the U-shaped portions of plates 54 and 56 of a die element 48 respectively defining the lower'ends of grooves 58 and 60 thereof. The outer end of the trough 69 of a die element 48 extends outwardly of outer plate 54 and can be beveled as indicated at 71 in FIGS. 2 and 4 to facilitate its overlapped connection to an outlet spout 72' of a manifold 74 that supplies molten cladding material such as aluminum from a metallurgical furnace (not shown) to the die trough 69 during operation of the equipment of system 10. Cladding plate 56 is preferably made from a suitable copper alloy to facilitate cooling and extraction of heat from the molten cladding material as it is cast in place between opposed flange surfaces of base element l: and the associated plate 56 of the die element of a die. Base plate 54 of a die element 48 can be provided with a hollowed-out interior (not shown) for enabling the circulation of coolant such as waterfor cooling plate 56 of the die element.

The lower end of the die element 48 ofa die 18 is advantageously adjustably connected to the inner end of the carriage 46. The outwardly facing side of a plate 54 at its lower end of the die element 48 of a die 18 includes an outwardly extending protrusion or boss 72. Opposed vertical sides 74 of the protrusion 72 of the plate 54 of a die 18 diverge in a direction towards the outer end of the die as indicated in FIG. 2. Opposed side portions 76 of the carriage 46 of a die 18 at the inner end of the carriage thereof are beveled in such fashion as to constitute a complementary outward extension of the outwardly divergent opposed sides 74 of the dovetail protrusion of 72 of the associated plate 54 of the die. A pair of somewhat L-shaped lugs 78 extend between and are clampingly connected to opposed sides of the protrusion of the die element 48 of a die 18 and the opposed sides of an associated carriage 46 of the die at the inner end of the carriage.

The opposed inside faces of a pair of die lugs 78 include opposed surfaces 80 that converge in a direction towards the inner end of the die 18. These opposed and convergent surfaces of die lugs 78 are complementary to the opposed side surfaces 74 and 76 of protrusion 72 and the carriage 46 associated therewith. A pair of bolt-nut assemblies 82 are passed through aligned openings in a pair of opposed lugs 78 and the inner end of an associated carriage 46 to loosely assemble the lugs to the'inner end of the carriage. When die protrusion 72 is inserted between the opposed pair of lugs 78 loosely connected to the inner end of an associated carriage 46 a die element 48 can be clampingly connected to the inner end of the associated carriage upon appropriate tightening of bolt-nut assemblies 82.

In securing a die element 48 to its associated carriage 46 the lower end of the die element is disposed slightly above the bottom 47 of the associated carriage so as not to interfere with the slidable engagement of the bottom 47 of the carriage with the top surface of framework plate 36 during adjustment of carriage 46 on plate 36. A lug 78 of a die 18 has a length substantially equal to the length of the protrusion of the die so as to provide maximum clamping engagement between protrusion side 74 and lug surface 80 associated therewith. The outer upper corner ends of a lug 78 may be beveled as indicated at 84 in FIG. 4.

In still another advantageous embodiment of the invention the mold system involves use of a die adjusting apparatus 22. The adjusting apparatus includes a shaft 86 that extends between opposed upper and lower sides of framework plate 36 as depicted in FIGS. 2 and 4. A shaft support block 88 is provided with a threaded aperture 89 for journably receiving either end of a shaft 86 in the manner illustrated in FIGS. 2 and 5. Shaft 88 has a diameter that substantially corresponds to the width of the U-shaped groove 50 of the carriage 46 of a given die device 18. The top surface of framework plate 36 adjacent the upper and lower sides thereof is cut away so as to define upper and lower dovetail grooves or ways 90. Each groove 90 extends fully between the left and right ends of the framework plate in the manner shown in FIGS. 2 and 4-6. An annular guideblock 92 insertable in either end of a groove 90 is of stepped configuration.

As noted in FIG. 6 the enlarged bottom portion 94 of block 92 has a diameter that approximates the linear distance between opposed inner side portions 96 of framework plate 36 that define the enlarged portion of a groove 90. The reduced upper portion 98 of a block 92 has a diameter that approximates the linear distance between opposed flange portions 100 of plate 36 defining the upper necked-in portion of a dovetail groove 90 all as depicted in FIG. 6. Thus upon insertion of a way block 92 at one end of groove in themanner illustrated in FIGS. 2 and 5 the way block 92 can be slidably disposed within the groove. Cap screws 102 passed through aligned openings in a guideblock 92 and the bottom 104 of a shaft block 88 are used to lock guideblock 92 to shaft block 88.

When a way block 92 is inserted in a groove 90 and affixed to a given shaft block, the bottom 104 of such shaft block is held in slidable engagement with the top of framework plate 36. When a pair of blocks 88 are slidably connected to the top of plate 36 an intermediate portion of shaft 86 extending between and journably connected to the pair of blocks 88 is inserted in appropriate fashion within the U-shaped groove 50 of a die carriage 46. This arrangement means then that as blocks 88 are moved shafts 86 and carriage 46 connected thereto will be moved accordingly.

Since the distance between the lower point of the U- shaped groove 50 of a die carriage and the bottom 47 thereof is substantially equal to the distance between the lower point of the aperture 89 of a block 88 and the bottom 104 thereof, the carriage bottom 47 is positive- 1y held in slidable engagement against the top of plate 36 when the carriage 46 is advanced together with the shaft 86 between the left and right ends of the framework plate 36.

Adjusting apparatus 22 further includes an actuator means 103 for effecting controlled advancement of the pair of blocks 88 between the ends of plate 36. An actuator means 103 is generally comprised of a pair of spaced L-shapedbrackets 104 and a fluid actuator 106 interposed between and pivotally connected to the pair of brackets 104. The pair of brackets are affixed in parallel spaced relationship to each other on the top and at a corner of plate 36 and in centered relation to one end of groove 90 in the manner illustrated in FIG. 2. Actuator 106 includes a fluid cylinder 108 and a double acting piston rod subassembly 110. A pair of blocks 112 are connected to opposite ends of cylinder 108. A pair of rods 114 extend between and are connected to the opposed pair of blocks 112 for clampingly securing the pair of blocks to the opposed ends of cylinder 108. A yoke element 116 has an intermediate portion 118 provided with a central aperture 120 and opposed end apertures 122 for respectively receiving intermediate portions of cylinder 108 and intermediate portions of the rods 114 during assembly of cylinder 108 and the pair of rods l14 to yoke 116 in an appropriate manner as illustrated in FIGS. 2 and 6. Upstanding and opposed leg sections 126 of brackets 104 are provided with apertures 128 for pivotally mounting and receiving the opposed shaft ends 124 of yoke 116.

The rod end 130 of the piston rod subassembly 110 extends outwardly from the right end of cylinder 108 and through an aligned opening in right block 112 as viewed in FIG. 2. The outer reduced and threaded end 132 of the rod 130 of piston rod subassembly 110 is threadably connected to the left side of a shaft support block 88 as illustrated in FIGS. 2 and 5. If desired, a lock nut 134 can be provided for securing the threaded end 132'to block 88. By virtue of the actuator and block connection, movement of actuator elements, such as piston rod subassembly 110, in either direction will produce corresponding movements of the blocks 88 connected thereto along with the various shafts 86 carried by the blocks. Since actuator 106 is pivotally mounted on plate 36 in alignment with underlying groove 90 in plate 36 a malfunction of actuator 106 is effectively prevented and the circular configuration of the guide plates 92 precludes binding of plates 92 in a groove 90.

An adjustable stopdevice .129 engageable with a block 88 is used to precisely position the block in an advanced position during the advancement of the mounting apparatus towards the right end of a given die opening 16 as viewed in FIG. 2. Block 130 of this device is held by cap screws 132 and pins 134 to the top of plate 36. This block is disposed to partially cover the intermediate part of a groove in plate 36.

Although the major adjustment of the dies 48 relative to the workpiece are effected through actuators 103 final minute adjustments after operation of actuators 103 are accomplished by means of vernier-type devices as follows. Mounted in threaded opening 136 of block is a vernier bolt 138 having an enlarged head 140. Triangularly shaped pointers 142 are affixed to the top of block 130 at either end thereof by way of cap screws 144 in the manner depicted in FIGS. 2 and The enlarged head ofa bolt 138 is provided with the series of calibrated markings 148 that indicate various advanced positions of the clad applying portion 70 of a given die 18. By manually engaging and turning head 140 the operator can adjust the cap screw 138 of a given stop 129 in either direction with respect to the block thereof until the appropriate cap screw indicia marking 148 is aligned with its respective pointer 142. Adjustment of the bolts 138 on either side of stop 129 will produce the final minute adjustment of dies 48 required to maintain the desired space or gap A between the die face 70 and the web of workpiece w in order to regulate the thickness of the major portion 18 of cladding C. If desired a lock screw 149 is threadably connected to either end of stop block 130 and is adapted to clampingly engage the threaded shank of a cap screw 138 associated with either end of the stop block so as to lock the cap screw in an adjusted positron.

In addition to the above described equipment a die biasing mechanism 28 is interposed between and connected to each shaft 86 in the areas of and on each side of a die 46. The biasing mechanism includes a pair of split annular collars 150 clamped about a shaft 86 by a bolt-nut assembly 152 at a distance equidistant on either side of the transverse axis 153 of opening 16 at a given station S Spring 154 is disposed about a shaft 86 and interposed between and compressed between a carriage 46 or carriage washer 156 associated with shaft 86 and a collar 150 affixed thereto. Thus a pair of springs 154 biasingly urge their associated carriage into a centered position as regards the transverse axis 153 of the opening 16 at a given station 8. By reason of the die element 48 of a die having a width less than the distance between opposed inner flange surfaces of a workpiece w a die element 48 of a die 18 defines a gap 3; of preselected size between one side of the die element and the opposed adjacent inner flange surface of a workpiece 3! when the die element is advanced to its normal cladding position.

The chain hoist 14 used to lower and raise the rails relative to the cladding dies includes a swivel hook 158' that can fit within aperture 16' located in the upper end of workpiece I. It is understood of course that when mold system 10 includes a series of cladding stations a common hoist can be provided for simultaneously advancing a plurality of workpieces into and through the opening 16 of the various cladding stations S.

The mold system of the present invention can further include a guide device 30 having guide rollers of the type disclosed in the aforesaid co-pending Patent application Ser. No. 881,169 of Richter et al. located adjacent the inlet side of mold assembly 12. These guide rollers of device 30 are only schematically and generally indicated in FIG. 1. A first set of rollers 160 engage exterior surface portions of the right-hand flange 12 of workpiece E while the second pair of rollers 162 are resiliently mounted and disposed at right angles to the first pair of rollers 160. The second pair 162 engage opposed flange edges of the right-hand flange 12' of a workpiece Q11. A third pair of resiliently mounted rollers 164 are disposed opposite to and spaced from the first and second pair of rollers 164 for engaging exterior surface portions of the left-hand flange 12' of workpiece Y1. By reason of the cooperative rolling engagement between the three pairs of rollers 160, 162 and 164 of device 30 a workpiece w is guided in general alignment into, through and out of the opening 16 of a mold assembly and in predetermined spaced relationship A with respect to die 18 associated with the opening thereof during operation of the system as shown in FIGS. 1-2 and 4. Inasmuch as further details of rollers 160, etc. are not believed necessary for an understanding of the improved resiliently biased die elements 48 of the instant invention reference can be made to the aforementioned copending Patent application Ser. No. 881,169 filed Dec. 1, 1969, for further details of these rollers.

During operation of the instant system the following takes place. As a workpiece w is moved between a pair of opposed dies 18 molten cladding material Q is directed from a metallurgical furnace (not shown) to manifold 74' and ultimately through spout 72 and the trough 69 of'a die 18 and then between the web of the workpiece and a die face 70.

When a workpiece E is advanced through the opening between opposed dies 18 the workpiece may periodically shift in a direction laterally of the dies due to geometrical variations in the workpiece along its length. Such lateral shifting of the workpiece will cause the gaps X to expand or contract on the various sides of die element 48 all as indicated by dotted lines at the upper part of the station shown in FIG. 2. Because of the biasing of the dies 18 if a workpiece should shift in a lateral direction greater than the distance of .a preselected gap X ofa given die 18, the die will tend to shift also and center itself. In any event excessive pressure and abraiding contact between a given die 18 and the adjacent inner flange surface of a workpiece E will be prevented. At the same time excessive exudation of clad material between the other side of the die and the adjacent inner side flange surfaces of a workpiece E is minimized. As indicated in FIG. 1 exudation of clad material between a given side of the die element 48 of a die 18 and the adjacent inner flange surface of a workpiece at most forms a slightly raised strip or burr l of clad material on a clad workpiece )1 at an exterior side edge of the major portion 18' of the clad material. Slightly raised strip portion I normally does not interfere with the use of a clad rail l as part of an electric railway system, etc. or materially affect the electrical properties of the clad rail. If desired, a raised strip 1, however, can be removed by an appropriate deburring device or tool.

The aforesaid self-centering characteristics of the dies 18 mean that substantially uniformly clad rails can be produced on a mass production basis and at relatively high production rates which may be required to make such clad rails economically feasible for use in mass transit systems.

The gap 3( can be on the order of one thirty-second of an inch while the gap A can be on the order of about five-eighths inches. In the above situation it has also been found that the die element 48 of the given die can have a width of about 3 inches while the rail E that was clad under the above operating conditions had an overall width between opposed flanges of about 3% inches.

The biasing of the die elements 18 has a further advantage which occurs during removal of the workpieces from the casting station by way of the hoist.

In other words, when hoist 14 withdraws the clad rail from opening 16 and raises it upwardly the resiliently mounted dies 18 can be brushed against and moved aside without scoring or scratching the cladding material now applied in solid form to the rail.

Advantageous embodiments of the mold system have been disclosed and described. Various changes and modifications can be made therein without departing from the appended claims wherein:

What is claimed is:

I. In a mold system employing a cladding die for applying a cladding material to an elongated metallic rail element and the like, the combination of a cladding mold assembly including a cladding die means and means for directing the rail element to be clad into and through the mold assembly and past said cladding die means, adjustable shaft means carried by said mold assembly for supporting said die means on said mold assembly and for selectively moving said die means relative to said mold assembly into a pocketed part of the rail element and for maintaining said die means at a predetermined spaced relationship with respect to said pocketed part of the rail element to define and maintain a gap of preselected size between said die means and the said pocketed part of the rail element as the rail element moves past said die means, pouring means for introducing molten cladding material into said gap, and spring biasing means connected to said adjustable shaft means and said die means for causing said die means to float along said shaft means relative to the rail element and to center itself relative to the rail element irrespective of variations in the cross sectional configuration of the rail element along its length as the rail element moves past said die means.

2. A system as set forth in claim 1 including common means for alternately directing the rail element to be clad into and through the mold assembly and then withdrawing the clad rail element from the mold assembly.

3. A system as set forth in claim 1 in which said die means is comprised of a pair of cladding dies located on opposing sides of the rail element.

4. A system as set forth in claim 1 in which said die means includes a carriage supported by a framework of said mold assembly and connected to said adjustable shaft means.

5. A system as set forth in claim 1 in which said adjustable shaft means includes an actuator means for advancing said die means from a retracted position to an advanced position.

6. A system as set forth in claim 3 including a common means for simultaneously adjusting both cladding dies relative to said rail element.

7. A system as set forth in claim 1 in which said adjustable shaft means includes stop means for precisely positioning said die means in an advanced position relative to the rail element.

8. A system as set forth in claim 1 wherein said spring biasing means comprises coil spring means.

9. A system as set forth in claim 1 wherein said system includes a plurality of pairs of cladding dies together with hoist means for raising and lowering separate rail elements relative to a given pair of cladding dies.

10. A cladding die station for applying a cladding material to an elongated metallic rail element and the like, said station comprising a cladding mold assembly, said mold assembly including a cladding die means, adjustable shaft means disposed on said mold assembly and connected to said die means for supporting said die means on said mold assembly and for adjustably and slidably moving said die means relative to said mold as sembly into a pocketed part of the rail element and for maintaining said die means at a predetermined spaced relationship with respect to said pocketed portion of the rail element as the rail element moves past said die means, and spring biasing means connected to said adjustable shaft means and said die means for causing said die means to float along said shaft means relative to the rail element and to center itself relative to the rail element being clad irrespective of variations in the cross sectional configuration of the rail element along its length as the rail element moves past said die means.

1 l. A station as set forth in claim 10 in which said die means is comprised of a pair of cladding dies located on opposing sides of the rail element.

12. A station as set forth in claim 10 in which said die means includes a carriage supported by a framework of said mold assembly and connected to said adjustable shaft means.

13. A station as set forth in claim 10 in which said adjustable shaft means includes an actuator means for advancing said die means from a retracted position to an advanced position.

14. A station as set forth in claim 11 including a common means for simultaneously adjusting both cladding dies relative to the rail element being clad.

15. A station as set forth in claim 10 in which said adjustable shaft means includes stop means for precisely positioning said die means in an advanced position relative to the rail element.

16. A station as set forth in claim 10 wherein said spring biasing means comprises coil spring means. 

1. In a mold system employing a cladding die for applying a cladding material to an elongated metallic rail element and the like, the combination of a cladding mold assembly including a cladding die means and means for directing the rail element to be clad into and through the mold assembly and past said cladding die means, adjustable shaft means carried by said mold assembly for supporting said die means on said mold assembly and for selectively moving said die means relative to said mold assembly into a pocketed part of the rail element and for maintaining said die means at a predetermined spaced relationship with respect to said pocketed part of the rail element to define and maintain a gap of preselected size between said die means and the said pocketed part of the rail element as the rail element moves past said die means, pouring means for introducing molten cladding material into said gap, and spring biasing means connected to said adjustable shaft means and said die means for causing said die means to float along said shaft means relative to the rail element and to center itself relative to the rail element irrespective of variations in the cross sectional configuration of the rail element along its length as the rail element moves past said die means.
 2. A system as set forth in claim 1 including common means for alternately directing the rail element to be clad into and through the mold assembly and then withdrawing the clad rail element from the mold assembly.
 3. A system as set forth in claim 1 in which said die means is comprised of a pair of cladding dies located on opposing sides of the rail element.
 4. A system as set forth in claim 1 in which said die means includes a carriage supported by a framework of said mold assembly and connected to said adjustable shaft means.
 5. A system as set forth in claim 1 in which said adjustable shaft means includes an actuator means for advancing said die means from a retracted position to an advanced position.
 6. A system as set forth in claim 3 including a common means for simultaneously adjusting both cladding dies relative to said rail element.
 7. A system as set forth in claim 1 in which said adjustable shaft means includes stop means for precisely positioning said die means in an advanced position relative to the rail element.
 8. A system as set forth in claim 1 wherein said spring biasing means comprises coil spring means.
 9. A system as set forth in claim 1 wherein said system includes a plurality of pairs of cladding dies together with hoist means for raising and lowering separate rail elements relative to a given pair of cladding dies.
 10. A cladding die station for applying a cladding material to an elongated metallic rail element and the like, said station comprising a cladding mold assembly, said mold assembly including a cladding die means, adjustable shaft means disposed on said mold assembly and connected to said die means for supporting said die means on said mold assembly and for adjustably and slidably moving said die means relative to said mold assembly into a pocketed part of the rail element and for maintaining said die means at a predetermined spaced relationship with respect to said pocketed portion of the rail element as the rail element moves past said die means, and spring biasing means connected to said adjustable shaft means and said die means for causing said die means to float along said shaft means relative to the rail element and to center itself relative to the rail element being clad irrespective of variations in the cross sectional configuration of the rail element along its length as the rail element moves past said die means.
 11. A station as set forth in claim 10 in which said die means is comprised of a pair of cladding dies located on opposing sides of the rail element.
 12. A station as set forth in claim 10 in which said die means includes a carriage supported by a framework of said mold assembly and connected to said adjustable shaft means.
 13. A station as set forth in claim 10 in which said adjustable shaft means includes an actuator means for advancing said die means from a retracted position to an advanced position.
 14. A station as set forth in claim 11 including a common means for simultaneously adjusting both cladding dies relative to the rail element being clad.
 15. A station as set forth in claim 10 in which said adjustable shaft means includes stop means for precisely positioning said die means in an advanced position relative to the rail element.
 16. A station as set forth in claim 10 wherein said spring biasing means comprises coil spring means. 